Metal-working tool



April 17, taza N. LUNDBERG \l 1 t e m t e m 6 L ou 09 T/l M. uw Rw o WD Lw Al Ti E? April 17, 1928. 1,666,500

N. l. LUNDBERG METAL WORKING TOOL Filed Dec, 6. 1924 6 Sheets-Sheet 2 Z9 6 Sheets-Sheet 5 lilllllllll N; l. LUNDBERG METAL WORKING TOOL Filed vec. e. 1924 Ap 17, 192s.

April 17, 192s. 1,666,500

N. I. LUNDBERG METAL WORKINGTOOL Filed Deo. 6. 1924 6 Sheets-Sheet 4 April 17, 1928.

1,666,500 N. l. I UNDBl-:RG

METAL WORKING TOOL Filed Dec. 6. 1924 6 Sheets-Sheet 5 qty April 17, 1928. 1,666,500

N. l. I UNDBERG METAL WORKING Tool..

Filed Dec. 6. 1924 6 Sheets-Sheet 6 1J" LgJ/Y.

52 @7i 50a/.I 59 'E 37 o' 46 g5 M QZ Patented Apr. 17, 1928.

UNITED STATES PATENT OFFICE NILS IVAR LUNDBERG. OF MADISON, WISCONSIN, ASSIGNOR TO GISHOIT MACHINE COMP A.NY, OF MADISON, WISCONSIN, A CORPORATION OF WISCONSIN.

METAL-WORKING TOOL.

Application led December 6, 1924. Serial N'o. 754,299.

This invention relates to metal working tools, and has reference more particularly to power-operated tools adapted to cut or grind either flat or curved surfaces (convex or concave) on a piece of work. In its chief intended application, my invention is embodied in a machine for grinding the arcuate surfaces of such articles as the links and link blocks employed in locomotive link motion gears, and the like; but the operative principle of the invention is capable of embodiment in milling machines and shapers or gear planers; and hence, while I have herein illustrated and described the invention as embodied in a link grinding machine,

it should be understood that the novel fea--4 tures thereof,and especially the mechanism whereby the grinding of concave, flat and convex surfaces is effected by a simple tilting adjustment of a guide bar or rail by which the arcuate or horizontal paths of travel of the work carrier are determined and controlled, may readily be embodied in cutting, milling, planing and other metal working tools.

The principal object of the present invention is to provide, in a tool of the character above-indicated. a simple, improved and readily adjustable mechanism whereby the work holder or carrier may be caused to reciprocate transversely of the power-driven tool in either a straight plane or a curved or arcuate plane, whereby to out or grind either a flat surface on the work or concave or convex surfaces of varying degrees of curvature.

Another more specific object is to provide, in such a machine, a simple and improved mechanism through which, when the work table has been moved to a position to bring the work into-proper relation to the tool, t-he work table feed is thrown out and the feed of thetross slide (which carries the work holder) is simultaneously thrown in. Still other objects and attendant advantages of the invention will be apparent to persons skilled in the art to which it relates from a consideration of the following detailed description, taken in connection with the accompanying drawings wherein I have illustrated one practical embodiment of the principle of the invention, and in which- Fig. 1 is a perspective elevation of a link grinding machine embodying the principle of the invention;

Fig. 2 is a side elevation of the same;

Fig. 3 is a rear elevation, viewed from the left of Fig. 2;

Fig. 4 is an enlarged view partly in side elevation and partly in longitudinal section, showing the pivotal mountlng of the work holder cradle and, in part, the work table and cross slide feed and reversing mechanisms;

Fig. 5 is a sectional plan showing, on an enlarged scale, the work table and cross slide feed and reversing mechanism which appear at the right of Fig. 4;

Fig. 6 is a detail in horizontal section on the line 6 6 of Fig. 4;

Fig. 7 is a detail view in side elevation, partly in vertical section, of a manually operated device for locking the cross slide reversing lever in neutral position;

Fig. 8 is an enlarged vertical section on the line 8-8 of Fig. 3;

Fig. 9 is a transverse section on the line 9 9 of Fig. 8;

Fig. l0 is an enlarged fragmentary rear elevation, partly in vertical section to show the mechanism for vertically adjusting the knee of the machine to maintain the work engaged with the tool as the former is ground off or cut away by the latter.

Fig. 11 is a view similar to Fig. 3, but showing the work holder cradle and the trolley mounted thereon at the limit of its left hand travel;

Fig. 12 is a detail view illustrating the pivotal attachment of a cam block to a plunger stem controlled thereby; and

Fig. 13 is an enlarged view partly in elevation and partly in vertical section of a part of the trolley and guide bar adjusting mechanism shown in Fig. 8.

Referring to the drawings, 10 designates the head frame, on horizontal ways 11 on which are mounted the carriage 12 supporting the tool spindle 13 and the bearings and motor for the latter; these features all bein of known and ordinary construction and with the details of which the present invention is not concerned. On the forward end of the spindle 13 is an emery wheel 14 constituting, in the instance shown, the grinding element. Y

On vertical ways 15 on the rear face ofthe head frame 10 is mounted the knee 1G, on parallel ways 17 of which (F ig. 3) ismounted the work table 18 reciprocable toward and from the head frame 10. In ways 19 (Fig. 4) on the upper surface of the work table 18 is mounted the cross slide 20, this latter travcling crosswise of the work table 18. Mounted in and crosswise of the cross slide 20, and adjustable lengthwise of the latter by bolts 21 (Fig. 4) is a hollow 'bearing sleeve 22, carrying bushings 23 inthe ends thereof in which is journaled a shaft 24, the ends .of which project beyond the bushings 23. On the projecting ends of the shaft 24 is mounted the work holder or carrier; the same comprising, as shown, a hollow inverted cradle member 25, and a flat generally rectangular plate 26 attached to the forward side of the cradle 25 by bolts 27 (Fig. 3). The front face of the plate 26 is formed with the usual undercut grooves 28 to receive the fastening bolts 29 of the work clamps or grips 30. In the illustration shown in the drawing, the work clamps or grips support the longitudinally slotted link of a locomotive link motion gear, the arcuate surfaces of the slot being ground by the emery wheel 14 to a i smooth fit with the usual link block (not shown).

As best shown in Fig. 3, the rear wall of the cradle 25 is extended at one end for some distance, and terminates in a widened end portion 25 formed on its rear face with ay vertical undercut slot 31 (Figs. 8 and 9), in which is housed an adjusting screw 32, said screw being journaled in a bearing 33 on the upper end of the extension member 25 and formed with a squared upper end 32 for the application of a wrench. The screw 32 is `threaded through a nut 34 that is slidably mounted in the slideway 31.

On the rear of the work table 18 is secured a block 35 on which is a central vertical standard 36 (Figs. 3 and 4) formed with an integral horizontal extension 3G lying parallel with the rear wall of the cradle 25 and terminating in a widened end portion 3al in which is formed an arcuate slot 37. In the standard 36 is mounted a short shaft 38, on the inner end of which is pivotally mounted one end of astraight guide bar 39 of a sutiicient length to considerably overhang one side of the machine frame, as shown in Fig. 3. The outer side of the guide bar 39 lies against the inner side of the slotted standard extension member 36; and the guide bar is adjustably clamped to said extension member by a. clamp screw 40, best shown in Fig. 13,'the headed end of whichl is non-rotatably secured in the guide bar 39, the clamp screw extending through the slot 37 and on its outer threaded end receiving a binding nut 41 preferably equipped with a handle 42 (Fig. 3) for tightening and loosening the saine. On one side of the slot 37 is ascale 43 marked in degrees of curvature, and cci-operating with this scale is a pointer 44, the shank of which is mounted on and non-rotatably secured to the clamp screw 40, as shown in Fig. 8. By the means last described, the guide bar 39 can be set and rigidly held in a horizontal position or in any inclined position below or above the horizontal permitted by the range of the slot 37.

(fo-operating with the guide bar 39 is a slide that is mounted in the nut 34. As herein shown, this` slide comprises a generally triangular trolley plate 45 rotatably mounted on a stud 46 (Fig. 8), the stem or shank 46 of which is fitted into a transverse slot in the nut 34 so as to be securely held by the latter, and is apertured for the passage therethrough of the screw 32. On the upper end of the trolley plate 45 is a trolley wheel 47 journaled on an eccentric stud 47 turnable to provide adjustment and compensation for wear; said wheel riding on the up per side of the guide bar 39, and on the lower end of the trolley plate 45 are jour-V naled a pair of similar trolley wheels 48 that ride on the lower side of the guide bar 39.

Attached to the top of the cross slide 20 by a screw 49 (Figs. 8 and 9) is a strip 50 longitudinally slotted for the passage of screw 49 and having a squared outer end which can be slid into a notch 50 in the cradle extension member 25 to lock the cradle in central and horizontal position while making the required angular adjustment of the bar 39; the central position of said cradle being determined by a line 25a on the side of the cradle (Fig. 3) coinciding with a pointer 35 attached to the block 35.

From the foregoing it will be seen that when the guide bar 39 is set at a downward inclination, as shown in Fig. 3, as the cross slide and cradle reciprocate, the latter will also be oscillated on its axis 24, so that the wheel 14 will cut or grind a concave surface on the portion of the work engaged with the upper side of the tool, and a convex surface on the portion of the work engaged with the lower side of the tool. If the guide bar 39 be adjusted to the zero point of the scale, which corresponds to a horizontal position of the guide bar, or one parallel with the path of travel of the cross slide` there will be no oscillation of the cradle, and the tool will cut or grind only fiat surfaces on the work. lf the bar 39 be adjusted to an upwardly inclined position, above the zero point of the scale, the combined reciprocating and oscillating movement of the cradle will cause the tool to cut or grind a Convex surface on that portion of the work engaged with the upper side of the tool, and a concave surface on the portion of the work engaged with the lower side of the tool. Mani- ,festly, the degrees of curvature of these surfaces depend upon the position of the guide bar 39, and the required curvature is read1ly obtainable through the scale and index pointer.

In setting up a job, in order to lnsure cutting or grinding in a symmetrical arc, the cross slide and cradle are first placed in central and horizontal position, wherein the axes of the tool 14, cradle pivot 24, and guide bar pivot 38`are all in a common vertical plane, and locked therein as described, and by then turning the screw 32 the guide bar 39 is then set at the required degree of curvature as shown by the scale 43. The

lacing of the cradle in horizontal position 1s effected by manipulating the adjusting screw 32. in which position of the cradle the axis of the tool 14 coincides with the transverse center of the work. as shown in Figs. 1 and 3, and hence, after the locking strip 50 has been retracted. the subsequent reciprocations of the cross slide and cradle carrying the work insure the cutting or grinding of symmetrical curved surfaces on both sides of the center.

The machine herein shown includes mechanism for moving the work table 18 to bring the work into correct position relatively to the tool and mechanism for effecting the automatic reciprocation ofthe cross slide and work holder. For greater convenience in the manipulation of the machine, I have also provided a simple manually operated mechanism by which, through a single movement of a lever, the work table feed may be thrown out and the cross slide feed thrown in, or the cross slide feed thrown out and the work table feed thrown 51 designates the feed screw of the work table 18, and 52 the feed shaft of the cross slide 20, said shaft carrying a pinion 54 (Fig. 4) driving a rack 55 on the under side of the cross slide. 56 (Fig. 4)- designates a power-driven shaft from which the movements of the work table and cross slide are transmitted. On this shaft 56 is a bevel gear 57 meshing with and driving two bevel gears 58 and 59 loose on a short shaft 60 `iournaled in line with the work table feed screw 51. the shaft 60 having a hollow extension 61 telescoping with one end of the feed screw 51. On the inner \faces of the bevel gears 58 and 59 are clutch members 62 and 63 resl'iectively adapted for co-opcration with a double-faced clutch 64 splined on the shaft 60. On the inner end of the tubular shaft extension 61 is a clutch member 65 that co-operates with a clutch member 66 splined on the stem of the feed screw 51. Then the clutch member 66 is engaged with the clutch member 65 4and the clutch member 64 is engaged with one or the other of the clutch members 62 and 63, the feed screw vis driven in a direction to move the work table outwardl or inwardly. The clutch member 64 is shi ted by a lever 67 (Fig. 5) pivoted at 68 on the top of the knee 16 and connected to a link 69 carrying a clutch shifter 70 (Fig. 6) engaged with the clutch member 64. The lever 67 is formed witha handle 71 overhanging one side of the knee 16, by which the clutch 64 is manually operated to start, sto and reverse the movement of the work tab e.

The ldrive shaft 52 of the cross slide is also driven from the short shaft 60 by the transmission shown in Fig. 4 and comprising a. spur pinion 72 keyed to the outer end of the shaft 6() driving a spur vgear 73 keyed to a short tubular shaft 74 journaled ina fixed bearing 75; the tubular shaft 74 having on its inner end a clutch member 76 cooperating with a clutch member 77 splined on the shaft 52. M anifestly, with the clutch members 76 and 77 engaged, the shaft 52 is rotated, and the cross slide caused to travel in one direction or the other from the shaft 56, accordingly as the clutch 64 is engaged with the gear clutch 62 or the gear clutch 63.

In Figs. 4 and 5 I show a simple hand-operated mechanism for throwing in the clutch 66 and throwing out the clutch 77, 0r vice versa, or throwing both clutches into neutral, by a single swing of a hand lever. ring to Fig. 4, 78 and 79 designate a pair of parallel hars mounted for sliding movement, the bar 78 carrying a clutchshifter 80 engaged with the clutch 77 and the har 79 carrying a clutch shifter 81 engaged with the clutch 66. 82 designates a shaft journaled in suitable bearings and carrying at its inner end a disc or plate 83 formed with diametrically opposed notches that straddle pins 84 and 85 on the bars 78 and 79 respectively. On the other end of the shaft 82 is an angularly bent operating handle 86. )Vith the parts in the position shown in Fig. 4, wherein the clutch 77 is engaged and the clutch 66 disengaged, by depressing the handle lever 86 the clutch 77 is first disengaged, placing both clutches in neutral position, and on a further downward swing of the handle lever 86 the clutch 66 is engaged. On the upper or reverse swing of the handle lever 86 the clutches 66 and 77 are manipulated in the reverse order.

In priming the machine for work, the lever 67 is first swung by hand to drive the shaft 60 in the direction required for either the inward or outward movement of the work table, and the hand lever 86 is swung downwardly to throw in thc clutch 66 and at the same time unclutch the clutch 77. )Vhcn the work table has thus brought the work into proper relation to the tool, the hand lever 86 is swung upwardly` disconi'iecting the clutch 66 and throwing in the clutch 77, thus starting the traverse of the cross slide; and thereupon the knee 16 is adjusted up- Refer# lill) wardly or downwardly as may be required (by a sim le mechanism hereinafter described) to ring and maintain the tool in contact with the surface of the work to be cut or ground.

The reciproeatory or to 'and fro travel of the cross slide is automatically eiected by a simple -mechanism which automatically shifts the clutch lever 67 at the end of each travel of the cross slide and reverses the direction ot' rotation of the cross slide drive shaft 52. {eiicrring to Fig. 4, in the shaft 74 is cut a spiral gear 87 driving an under l ving spiral gear 88 fast on a cross shaft 89 Fig. 5), this latter carrying on its outer end a pinion 90 driving an internal gear 91 on the rear side ot an indexing disc 92. On the periphery of the disc 92 are adjustably mounted a pair of tappets 93 and 94 adapted to alternately strike a laterally projecting pin 95 on a bar 96 slidably mounted in brackets 97 on the knee 16. Secured to the inner face of the bar 96 (Fig. 5) are a pair of hollow casings 98 and 99 in which are mounted spring-pressed pins 100 and 101, respectively, the adjacent projecting ends of which lie on opposite sides of and in the. horizontal plane of the portion of the clutch shifting lever 67 lying between them. As the cross slide and work holder travel in one direction, the index disc 92 rotates until one of the tappets 93 and 94 strikes the pin 95 and thereby moves the bar 96 endwise until one of the pins 100 and 101 strikes the lever 67, thereby shifting the clutch 64 and reversing the direction of rotation of the cross slide driving shaft 52. Manifestly, the length ot travel of the cross slide and work holder is determine-d by the set of the tappets 93 and 94 on the indexing disc 92. For a long travel of the work holder to effect the grinding of a piece of work such as the link L, the tappets are set at a considerable angular distance apart. For the grinding of a shorter piece of work, the tappets will be set a correspondingly shorter angular distance apart.

In Fig. 7 is illustrated a simple device for locking the clutch lever 67 in neutral position, that is, a position in which the clutch 64 is disengaged from both of the clutches 62 and G3, and the machine is idle. This comprises a depending lug 102 on the lever 67 that is engaged by the concave upper face of a plungerA 103 slidably mounted in a guide 104 on the side of the knee 16 and pressed upwardly by a spring 105. A plunger stem 106 extends through the bottom of the guide 104 and at its lower end is pivotally attached to a cam block 107. An outwardly extending shaft 108 on the cam block 107 carries at its outer end a handle 109. By swinging the handle 109 downwardly, as indicated by the arrow in Fig. 7, the cam 107, acting on the bottom of the guide 104, retracts the plunger 103 from the' pathof the lug 102, and frees the lever 67. Of course, during the normal .operation of the machine the clutch lever remains freed, the lever locking mechanism being employed when the machine is idle or during the chucking and unchucking of the work to avoid accidental starting up of the machine.

AS the cutting or grinding of the work proceeds, since the tool 14 is stationary except for its rotative movement, it is necessary from time to time to gradually raise or -lower the work relatively to the tool. This is eti'ected by manually operated means for lifting and lowering the knee 16 and all oi' the parts carried thereby. Referring to Fig. 10, 110 designates a rearwardly extending portion of the base of the head frame 10, on which is formed a hollow pedestal 111 centrally apertured to receive and non-rotatably carry a nut 112. -lngaged with the nut 112 is a threaded shaft 113 journaled in a bearing 114 in the knee 16 and having fast on its upper end a bevel gear 115 engaged and driven by a bevel pinion 116 tast on the inner end of a horizontal shaft 117 journaled in a bearing 118 on the knee 16 and a bearing 119 on the side wall of the knee 16. On the outer end of the shaft 117 is a hand wheel 120. Keyed to the shaft 117 is a collar 121 the periphery ot which is provided with a scale 122 that cooperates with a fixed index mark 123 on the periphery ot' a stationary collar 124 encircling the shaft 117.

It is believed that the operative principle, manner of operation, and practical advantages of the present invention will be clear to persons skilled in the art from the foregoing description and the accompanying drawings. One of the most valuable features of the machine resides in the angularly adjustable guide bar 39. the cradle pivoted on the cross slide to oscillate in a plane at right angles to the plane of the latter, and the cradle trolley engaged with the guide bar 39, whereby, through the simple angular adjustment of the guide bar 39 it is possible to cut or grind arcuate surfaces (both concave and convex) of any predetermined degree of curvature Within the limits of adjustment ot the guide bar; or by adjusting the latter to a position parallel with the path of travel of the cross slide, to cut or grind a flat surface. Still another feature which cxpeditcs the practical use of the machine resides in the means, exemplified by the hand lever 86, and the mechanism operated thereby through which the traverse of the work table is thrown in or out and the feed ol' the cross slide is practically simultaneously thrown outl or in by a single manipulation of a manually operated part such as the handle lever 86.

Vhile I have herein described, and in the drawings illustrated, one practical embodiment of the principle of the invention which in practice'has been found to satisfactorily effectuate the stated purposes and objects theieo t', it is manifest that variations iii details ot' construction and arrangement may be inade `lwithout departing from the substance ol' the invention or lsacrificing any of the advantages thereof. Also, as before stated, by the employment ot' a milling cutter in lieu ol the eniery wheel 14, the invention may be embodied in a milling machine, and it can also be used on a shaper or gear planer to obtain a planed surface on any piece havingl an arc or a section of a circle or for cutting gear teeth on the saine. Hence, I reserve all such variations, modifications, and mechanical equivalents as fall Within the spirit and purview of the appended claims.

I claim- 1. In a machine for cutting curved surfaces on metal castings and the like, the coinbination with a stationary tool holder carrying a horizontal rotary cutting tool, of a vertically adjustable cross-slide support, a cross-slide on said support, means for reciprocating said cross-slide transversely of the axis of said tool, a work holder pivoted on said cross-slide on an axis parallel with the axis of said tool, and means for effecting an oscillating movement of said work holder in a vertical plane simultaneously with the reciprocating travel of said cross-slide.

2. In a machine for cutting curced Surfaces on metal castings and the like, the combination with a stationary tool holder carrying a horizontal rotary cutting tool, of a vertically adjustable cross-slide support, a cross-slide on said support, means for reciprocating said cross-slide transversely of the axis of said tool, a work holder pivoted on said cross-slide on an axis parallel with the axis of said tool, a stationary guide bar,

and a slide carried by said work holder engaged with said guide bar and operating, through such engagement, to oscillate said work holder during the reciprocating travel of said cross-slide.

3. In a machine for cutting arcuate surfaces on metal castings and the like, the combination with a stationary tool holder carrying a horizontal rotary cutting tool, of a vertically adjustable cross-slide support, a cross-slide on said support, means for reciprocating said cross-slide transversely of the axis of said tool, a work holder pivoted between its ends on said cross-slide on an axis parallel with the axis of said tool, a stationary straight guide bar inclined to the path of travel of said cross-slide, and a slide carried by said work holder engaged with said guide bar.

4. In a machine for cutting arcuate surfaces on metal castings and the like, the combination with a stationary tool holder carrying a horizontal rotary cutting tool, of a vertically adjustable cross-slide support, a

cross-slide on said support, means for reciprocating said cross-slide transversely of the axis ot said tool, a work holder pivoted between its ends on said cross-slide on an axish parallel with the axis of said tool, a straight guide bar, means for vertically adjusting said guide bar to different degrees of inclination to the path of travel of said cross-slide, and a trolley on said work holder engaged with said guide bar.

5. In a machine for cutting arcuate surfacesoininetal castings and the like, the combination with a stationary tool holder carrying a horizontal rotary cutting tool, of a vertically adjustable cross-slide support, a cross-slide on said support, means for reciprocating said cross-slide transversely of the axis of said tool, a work holder pivoted between its ends on said cross-slide on an axis parallel with the axis of said tool, a straight guide bar pivoted at one end thereof on said cross-slide support, means for adjusting said guide bar angularly to positions parallel with or oppositely inclined to the path of travel of said cross-slide, and a trolley on said work holder engaged with said guide bar.

6. In a machine for cutting arcuate surfaces on metal castings and the like, the combinationwith a stationary tool holder carrying a horizontal rotary cutting tool, of a vertically adjustable cross-slide support, a cross-slide on said support, mear'is for reciprocatinoi said cross-slide transversely of the axis of said tool, a work holder pivoted between its ends on and cross-wise of said cross-slide on an axis parallel with the axis of said tool, a stationary straight guide bar inclined to the path of travel of said crossslide, and a trolley on, and transversely adjustable of, one end of said work holder engaged with said guide bar.

7. In a machine for cutting arcuate surfaces 0n metal castings and the like, the combination with a stationary tool holder carrying-a horizontal rotary cutting tool, of a verticall adjustable cross-slide support, a cross-sli e on said support, means for reciprocating said cross-slide transversely of the axis of said tool, a work holder pivoted between its ends on and cross-wise of said cross-slide on an axis parallel with the axis of said tool, a straight guide bar pivotally mounted at one end in the vertical plane of the axis of said tool, means for shifting and securing the other end of said guide bar to and at points in, or to either side of, the horizontal plane of the guide bar pivot, and a trolley on said work holder engaged with said guide bar.

8. In a machine of the character described, the combination of a head frame, a tool holder mounted thereon, a knee adjustable in wa s on said head frame, a work table slidab y mounted on said knee, means for actuating said work table toward and from said tool holder a cross-slide on said work table, a Work holder on said cross-slide means for actuating said cross-slide, an

manually operable means acting by a continuous movement in one direction to interrupt said work table actuating means and start said cross-slide actuating means, and by a continuous movement in the opposite direction to interrupt said cross-slide actuating means and start said Work table actuating means.

9. In a machine for cutting arcuate surfaces on metal castings and the like, the combination with a relatively iixed tool holder carrying a rotary cutting tool, of a crosss1ide,means for reciprocatmg said cross-slide transversely of the axis of said tool, a work holder pivoted at its longitudinal center on said cross-slide on an axis parallel with the axis of said tool, said Work holder being formed with a transverse slot, a stationary straight guide bar adjustable to various degrees of inclination relatively to the path of Leeaaeo travel of said cross-slide, an adjusting screw journaled in and lengthwise of said slot, a nut slidable in said slot and engaged with said screw, a bearing member carried by said nut, and a trolley journaled on said bearing member and engaged with said guide bar.

l0. In a machine for cutting arcuate surfaces on metal castings and the like, the combination with a relatively fixed tool holder carrying a rotary cutting tool, of a crossslide, means for reciprocating said crossslide transversely of the axis of said tool, a work holder pivoted at its longitudinal center on said cross-slide to oscillate in aplane at right angles to the plane of said crossslide, a pivoted guide bar adjustable to various degrees of inclination relatively to the path of travel ofvsaid cross-slide, a trolley mounted on said work holder engaged with said guide bar, and means for locking said work holder in a predetermined position against oscillation preliminary to adjustment of said guide bar.

NILS IVAR LUNDBERG. 

